January 27 marks the 60th anniversary of the Allied liberation of the Nazi concentration camps. Commemorative ceremonies are slated in 13 countries throughout Europe, including France, Germany, Italy, and Poland, at the site of the Auschwitz camp; in Israel; and in the United States.

For the first time, the United Nations held a special Holocaust memorial session of the General Assembly on January 24, with Nobel laureate and Auschwitz survivor Elie Wiesel as a speaker. U.N. Secretary-General Kofi Annan reminded the gathering that while the Nazis targeted many groups, including the handicapped and homosexuals, "the tragedy of the Jewish people was unique. An entire civilization, which had contributed far beyond its numbers to the cultural and intellectual riches of Europe and the world, was uprooted, destroyed, laid waste."

As millions around the world pause this week to honor Nazism's victims, Mark Weber, director of the California-based Institute for Historical Review, America's central clearing-house of Holocaust revisionism, is writing his latest diatribe downplaying the Third Reich's campaign against Europe's Jews.

In recent years, there has been a rush to documentation before the remaining survivors die. Holocaust museums, scholars, and documentary filmmakers have amassed an enormous amount of evidence, including videotaped narratives such as the eyewitness accounts gathered by Steven Spielberg's Shoah Foundation project.

Yet even the cumulative weight of this vast documentation of Nazi atrocities hasn't budged Weber and his fellow Holocaust revisionists. Rather, because these last-minute first-person accounts perpetuate what they consider to be lies and distortions, the growing mass of testimony only fuels their contention that key events in the Holocaust never happened. In the revisionist mindset, the latest accounts, like the earliest, lack convincing evidence.

Weber first detected this so-called absence of proof 25 years ago, when he was shown aerial reconnaissance photographs of Auschwitz. "There were no piles of corpses, smoking chimneys, or masses of Jews awaiting death," Weber says. Yet, Wiesel and others claimed the photographs proved that "Jews were being killed, and that the Americans let it happen."

That's when Weber, who is now 53, began to question the "official view" of the "Holocaust story." "I had been aware of it growing up," he says. "I read `The Diary of Anne Frank'."

Weber found support for his skepticism in "The Hoax of the Twentieth Century: The Case Against the Presumed Extermination of European Jewry" by Paul Butz, the father of the American Holocaust denial movement. Weber says he remained unconvinced about the proof for a systematic genocide of the Jews presented in such works as the historian Raul Hilberg's "Destruction of the European Jews," as well as in visits to the Dachau and Mauthausen concentration camps.

"When it came to systematic extermination, the evidence was very thin," Weber says. Like other revisionists, he acknowledges that the Nazis deported large numbers of Jews and others to camps or ghettos, where they were subjected to brutal treatment and where many were killed or died of disease and malnutrition which he calls an inevitable consequence of war.

Weber, who holds a master's degree in European history from the University of Indiana, faults works such as Claude Lanzmann's documentary "Shoah," along with taped eyewitness accounts and museum archives, for spreading what he considers to be false claims, exaggerations, and imprecise statistics. He says they are tools in a "relentless" media campaign that has turned the Holocaust into an "icon," even a "secular religion," in which denying the Holocaust is a crime punishable by imprisonment in many countries. All of this activity promotes Jewish-Zionist political and financial interests, Weber maintains.

Novels and movies are, by definition, the least trustworthy. "Schindler didn't have a list," he says.

Instead, Weber, who briefly served as news editor of the Neo-Nazi magazine, "National Vanguard," relies on his own selection of sources-essays, papers, and scientific reports produced by Holocaust revisionists from the United States, Canada, France, Switzerland, and Australia, which are disseminated over the Internet and at IHR conferences (and which used to appear in the now-defunct "IHR Journal"), as well as writings by academics and journalists, many of them Jewish, who are critical of Israeli government policy.

Among the most influential revisionist documents are the 1988 Leuchter Report and its follow-ups, which profess to substantiate a core revisionist belief: that Jews, though brutalized and killed in large numbers, were not gassed in Nazi concentration camps. The report purports to provide scientific proof, based on analyses of scrapings collected at Auschwitz by Fred Leuchter, Jr., an authority on U.S. prison execution chambers, that Nazi gas chambers were used for fumigation and delousing, not for extermination, and that the purpose of the crematory ovens was to dispose of those who had died of illnesses such as typhus in a manner that would prevent further spread of disease.

Leuchter claims to have broken into facilities at the camp and documented the locations of forensic samples taken from the Auschwitz-Birkenau complexes, and a "control sample" at delousing facility #1, but he did not record the exact locations in his log. It is worth nothing that more than 40 years after the war, Leuchter found cyanide in those samples.